1. Field of Invention
This invention relates to devices that can detect small changes in distance between opposed surfaces and methods of detecting small distance changes between opposed surfaces using the devices.
2. Description of Related Art
Imaging devices include, for example, electrophotographic and electro graphic printers, ink jet printers and thermal printers. In these devices, an imaging substrate is fed into a feed path and conveyed through the apparatus to an imaging station for imaging. Multiple imaging substrates, such as paper sheets, are typically stored in stacks in the imaging apparatus. The substrates are separated from each other so that individual substrates are fed into the feed path for imaging.